Technical Field
The present application relates to the field of video encoding, and more particularly to a motion vector estimation method in video encoding.
Related Art
In current mainstream video codec standards (for example, MPEG4, H.264/AVC, and H.264/AVS) and relevant video processing applications (for example, superresolution and frame rate upsampling), most motion estimation methods scan image blocks in a two-dimensional video frame in a scan order from top to bottom and from left to right to search for a corresponding motion vector. Also, during estimation of each image block, a motion vector of an adjacent block in a region on the left of and above the image block is usually used as a spatial reference motion vector, a motion vector of an image block on lower right of a corresponding image block in a previous frame as a time reference motion vector, and then a strategy is adopted to select the most accurate one from reference motion vectors as an initial motion vector of a current image block. By utilizing this method, a motion vector estimated first can be transferred from an upper left image block to an image block in a lower right corner in a scan order from top to bottom and from left to right, so as to achieve an objective of refine a motion vector gradually.